CN115369455B

CN115369455B - Copper foil and production equipment and production method thereof

Info

Publication number: CN115369455B
Application number: CN202211025371.6A
Authority: CN
Inventors: 盛银莹; 单大勇
Original assignee: Institute of Corrosion Science and Technology
Current assignee: Institute of Corrosion Science and Technology
Priority date: 2022-08-25
Filing date: 2022-08-25
Publication date: 2023-07-21
Anticipated expiration: 2042-08-25
Also published as: CN115369455A

Abstract

The invention discloses a copper foil, and production equipment and a production method thereof, and belongs to the technical field of copper foil. The production equipment comprises an anode tank, a titanium anode plate and a cathode titanium foil; the titanium anode plate comprises a first titanium anode plate and a second titanium anode plate which are arranged in parallel up and down, a channel for a cathode titanium foil to pass through is formed between the two titanium anode plates, the two titanium anode plates are both positioned in the anode tank, titanium oxide films are respectively arranged on the upper surface and the lower surface of the cathode titanium foil, and the cathode titanium foil is used for depositing copper foil in the process of passing through the channel. The production method is based on the production of electrolytic copper foil on the surface of cathode titanium foil with titanium oxide film, the thickness of the obtained copper foil is not limited by the grain size of titanium matrix, and the production method has absolute advantage in the production of ultra-thin even ultra-thin copper foil with the thickness of not more than 5 mu m. In addition, the production mode of double-sided deposition copper foil is adopted, so that the production efficiency can be obviously improved, and the production cost can be reduced. The obtained copper foil has no pinholes, low warpage, fine and smooth rough surface unit cells, uniform structure and no obvious polishing scratch on the smooth surface.

Description

Copper foil and production equipment and production method thereof

Technical Field

The invention relates to the technical field of copper foil, in particular to a copper foil and production equipment and a production method thereof.

Background

The global new energy electric car industry and the 5G electronic information industry are developing at a high speed, and the lithium electric copper foil and the electronic copper foil are required to be thinner, stronger and tougher, but the reduction of the thickness and the improvement of the performance of the electrolytic copper foil also put higher requirements on the technology and the production.

The existing electrolytic copper foil production mainly adopts a roller type continuous electrolytic method, namely copper ions in copper sulfate electrolyte are continuously deposited on a cathode titanium roller rotating at a uniform speed and circumference under the action of an external electric field, and the electrolytic copper foil with a certain thickness can be obtained through stripping and winding.

However, the above method cannot effectively produce an extremely thin copper foil (4.5 μm) having high and stable properties.

In view of this, the present invention has been made.

Disclosure of Invention

One of the objectives of the present invention is to provide a copper foil production apparatus to solve the above-mentioned problems.

The second object of the present invention is to provide a method for producing copper foil using the copper foil production equipment.

The third object of the present invention is to provide a copper foil produced by the above method.

The application can be realized as follows:

in a first aspect, the present application provides a copper foil production apparatus comprising an anode tank, a titanium anode plate, and a cathode titanium foil;

the titanium anode plate comprises a first titanium anode plate and a second titanium anode plate which are arranged in parallel up and down, a channel for passing cathode titanium foil is formed between the first titanium anode plate and the second titanium anode plate, and the first titanium anode plate and the second titanium anode plate are both positioned in the anode tank;

the upper and lower surfaces of the cathode titanium foil each have a titanium oxide film, and the cathode titanium foil is used for depositing copper foil during passage through the passage.

In an alternative embodiment, the distance between the lower surface of the first titanium anode plate and the upper surface of the second titanium anode plate is 1-3cm.

In an alternative embodiment, the upper and lower surfaces of the cathode titanium foil each have a thickness of the titanium oxide film of not more than 100 μm, preferably 5 to 20 μm.

In an alternative embodiment, the copper foil production apparatus further comprises a supporting means for supporting the cathode titanium foil.

In an alternative embodiment, the support means comprises at least one set of first support members, all of which are arranged in the anode cell and support the portion of the cathode titanium foil located in the anode cell.

In an alternative embodiment, each set of first support assemblies includes a mating upper support member for abutting an upper surface of the cathode titanium foil and a mating lower support member for abutting a lower surface of the cathode titanium foil, respectively.

In an alternative embodiment, the inlet and outlet ends of the channel are each provided with at least one set of first support members.

In an alternative embodiment, the support means comprises at least one set of second support members, all of which are arranged outside the anode cell and support the portion of the cathode titanium foil located outside the anode cell.

In a second aspect, the present application provides a method for producing a copper foil, comprising: the copper foil production apparatus according to any one of the preceding embodiments is used for production.

In an alternative embodiment, the cathode titanium foil is passed through the channels at a constant speed under electrolysis conditions and copper foil is deposited on the surface of the cathode titanium foil within the channels during the passing.

In an alternative embodiment, the passing speed is not more than 10m/min, preferably 2-6m/min.

In an alternative embodiment, the electrolyte used to deposit the copper foil is a copper sulfate system electrolyte.

In an alternative embodiment, the copper sulfate system electrolyte includes a base component and an additive;

wherein, based on each L of electrolyte, the basic component comprises 350-360g/L of copper sulfate, 100-130g/L of sulfuric acid and not more than 10mg/L of chloride ions;

the additive comprises an agent A and an agent B, wherein the agent A comprises at least one of 50-200mg/L of hydroxyethyl cellulose, 10-100mg/L of polyethylene glycol, 40-60mg/L of polypeptide protein, 20-60mg/L of alkylated polyethyleneimine and 10-30mg/L of fatty amine ethoxysulfonate; the agent B comprises at least one of 5.0-10.0mg/L of polydithio-dipropyl sodium sulfonate, 20.0-100.0mg/L of 3-mercapto-1-propane sodium sulfonate, 1.0-10.0mg/L N, N-dimethyl-dithiocarbonyl sodium propane sulfonate and 2.0-6.0mg/L of thiazolidinedione.

In an alternative embodiment, the additive further comprises a C agent comprising at least one of 0.5-5.0mg/L of a thiazabenzene derivative, 0.5-5.0mg/L of an azapyridine derivative, and 0.5-5.0mg/L of a substituted hydrazine derivative.

In an alternative embodiment, the cathodic titanium foil is prepared by the following method: titanium oxide films are plated on the upper surface and the lower surface of the titanium foil substrate by adopting a surface oxidation mode.

In alternative embodiments, the surface oxidation regime includes anodic oxidation regime or high temperature oxidation regime.

In alternative embodiments, the current used in the anodization process is in the form of a direct current or a pulse.

In an alternative embodiment, the anodizing solution used in the anodizing process is configured of at least one of sulfuric acid, oxalic acid and lactic acid, or an electrolyte used for depositing the copper foil is used.

In an alternative embodiment, the voltage is 15-50V, the current is 0.5-2A, and the treatment time is 3-5min during the anodic oxidation.

In an alternative embodiment, the temperature is 400-600 ℃ and the treatment time is 1-3 hours during the high temperature oxidation.

In an alternative embodiment, the method further comprises mechanically or chemically polishing the titanium foil substrate prior to the surface oxidation.

In an alternative embodiment, the method further comprises stripping and rolling the cathode titanium foil deposited with the copper foil.

In an alternative embodiment, the method further comprises: and (3) oxidizing the cathode titanium foil obtained after stripping again for recycling.

In a third aspect, the present application provides a copper foil produced by the copper foil production method of any one of the preceding embodiments.

In an alternative embodiment, the copper foil has a thickness of no more than 5 μm.

The beneficial effects of this application include:

according to the method, the cathode roller in the prior art is replaced by the double-sided oxidized titanium foil to serve as a cathode, and the electrolytic copper foil is produced on the basis of the surface of the cathode titanium foil with the titanium oxide film, so that the thickness of the obtained copper foil is not limited by the grain size of a titanium matrix, the barrier of the thickness of the copper foil is overcome, and the method has absolute advantages in the production of ultra-thin even ultra-thin copper foil with the thickness not exceeding 5 mu m. In addition, the production mode of double-sided deposition copper foil is adopted, so that the production efficiency can be obviously improved, and the production cost can be reduced. The obtained copper foil has no pinholes, low warpage, fine and smooth rough surface unit cells, uniform structure and no obvious polishing scratch on the smooth surface.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings that are needed in the embodiments will be briefly described below, it being understood that the following drawings only illustrate some embodiments of the present invention and therefore should not be considered as limiting the scope, and other related drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.

FIG. 1 is a schematic view of a copper foil production apparatus provided herein;

FIGS. 2 and 3 are photographs of copper foil corresponding to example 2 in the test example of the present application;

fig. 4 and 5 are photographs of copper foil corresponding to comparative example 1 in the test example of the present application.

Icon: 1-titanium anode plate; 2-anode cell; 3-cathode titanium foil; 4-foil production; 5-peeling off the titanium foil; 6-supporting means.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present invention more clear, the technical solutions of the embodiments of the present invention will be clearly and completely described below. The specific conditions are not noted in the examples and are carried out according to conventional conditions or conditions recommended by the manufacturer. The reagents or apparatus used were conventional products commercially available without the manufacturer's attention.

The copper foil and the production equipment and the production method thereof provided by the application are specifically described below.

The inventors have studied and proposed that the reasons for the failure to effectively prepare an ultra-thin copper foil (4.5 μm) with high performance and stable performance using a roll-type continuous electrolytic method in the prior art include: on one hand, the method is limited by the grain size of the titanium roller, and on the other hand, the grinding and polishing process on the surface of the grinding roller is difficult.

Based on this, the present application creatively proposes a copper foil production apparatus including an anode tank 2, a titanium anode plate 1, and a cathode titanium foil 3 as shown in fig. 1.

The titanium anode plate 1 comprises a first titanium anode plate and a second titanium anode plate which are arranged in parallel up and down, a channel for the cathode titanium foil 3 to pass through is formed between the first titanium anode plate and the second titanium anode plate, and the first titanium anode plate and the second titanium anode plate are both positioned in the anode tank 2.

For reference, the distance between the lower surface of the first titanium anode plate and the upper surface of the second titanium anode plate may be 1-3cm, such as 1cm, 2cm, 3cm, or the like.

In some preferred embodiments, the upper surface of the titanium foil is 1cm from the lower surface of the first titanium anode plate and the lower surface of the titanium foil is 1cm from the upper surface of the second titanium anode plate when the cathode titanium foil 3 passes through the channel.

In this application, the cathode titanium foil 3 has titanium oxide films on both upper and lower surfaces, and the cathode titanium foil 3 is used to deposit copper foil during passage through the passage.

For reference, the thickness of the titanium oxide film on the upper and lower surfaces of the cathode titanium foil 3 is not more than 100. Mu.m, for example, 100. Mu.m, 80. Mu.m, 50. Mu.m, 20. Mu.m, 10. Mu.m, 5. Mu.m, or 2. Mu.m, and the like, and preferably 5 to 20. Mu.m.

The reason why the thickness of the titanium oxide film is controlled to not more than 100 μm in the present application is that: if the oxide film thickness exceeds 100 μm, the oxide film resistance increases, the cell voltage increases, and the energy consumption increases. And, when the thickness of the titanium oxide film is 5 to 20 μm, it can more effectively realize the preparation of the ultra-thin copper foil.

On the support, by adopting the titanium foil with double-sided oxidation instead of the cathode roller as the cathode, not only can the barrier of the thickness of the copper foil be overcome, but also the production efficiency of the copper foil can be improved, and the production cost can be reduced.

Further, the above copper foil production apparatus may further comprise a supporting means 6 for supporting the cathode titanium foil 3.

By way of reference, the support means 6 comprise at least one group (e.g. 1, 2,3 or more) of first support members, all of which are arranged in the anode cell 2 and support the portion of the cathode titanium foil 3 located in the anode cell 2.

Each group of first supporting components respectively comprises an upper supporting piece and a lower supporting piece which are matched, wherein the upper supporting piece is used for being abutted with the upper surface of the cathode titanium foil 3, the lower supporting piece is used for being abutted with the lower surface of the cathode titanium foil 3, and certain limiting and guiding effects can be achieved on the cathode titanium foil 3 through the cooperation of the upper supporting piece and the lower supporting piece, so that the cathode titanium foil 3 can uniformly and stably pass through the channel.

In some preferred embodiments, the inlet and outlet ends of the channel are each provided with at least one set of first support members. The number of the first supporting components which are specifically arranged at each end can be adjusted according to actual needs.

Further, the supporting device 6 may further include at least one set of second supporting components, where all second supporting components are disposed outside the anode tank 2 and support the portion of the cathode titanium foil 3 located outside the anode tank 2.

The specific positions and the number of the second support members disposed outside the anode tank 2 can be adjusted as required, and are not limited thereto.

In some specific embodiments, the support may be, by way of example and not limitation, a bearing.

It should be noted that, other structures not described in detail in the present application may refer to the related content of the roll-type continuous electrolysis method, and are not described herein in detail.

Correspondingly, the application also provides a copper foil production method, which comprises the following steps: the copper foil production equipment is adopted for production.

The production process comprises the following steps: under the electrolytic condition, the cathode titanium foil 3 is uniformly passed through the channel and copper foil is deposited on the surface of the cathode titanium foil 3 in the channel during the passing. Subsequently, the cathode titanium foil 3 deposited with the copper foil is peeled off and rolled up. Further, the cathode titanium foil 3 obtained after the peeling may be subjected to oxidation treatment again for recycling.

Specifically, the copper foil can be deposited on both sides of the double-sided oxidized titanium foil, the copper foil can pass through the anode tank 2 at a constant speed, the copper foil is deposited on the surface of the titanium foil at the opposite position between the two parallel anode plates, the deposition speeds of the upper surface and the lower surface are the same, the copper foil with the same thickness is deposited on both sides of the titanium foil, the copper foil with the same thickness can be obtained through stripping and rolling, the raw foil 4 (copper foil) with the same thickness and the stripped titanium foil 5 can be obtained, and the titanium foil can be recycled through washing and re-oxidation treatment, and continuous deposition production can be realized.

By way of reference, the above-mentioned uniform passing speed is not more than 10m/min, such as 10m/min, 9m/min, 8m/min, 7m/min, 6m/min, 5m/min, 4m/min, 3m/min, 2m/min or 1m/min, etc., preferably 2-6m/min.

The copper foil which has no pinholes, low warpage, fine rough surface unit cells, uniform structure and no obvious polishing scratch on the smooth surface is obtained through the optimized speed.

It should be noted that, other process steps or conditions in the deposited copper foil not described in the present application may refer to the related prior art, and are not repeated and limited herein.

In the present application, the electrolyte used for depositing the copper foil is a copper sulfate system electrolyte.

For reference, the above-mentioned copper sulfate system electrolyte may include, for example, a base component and an additive.

Wherein the base component comprises 350-360g/L (such as 350g/L, 355g/L or 360g/L, etc.), 100-130g/L (such as 100g/L, 105g/L, 110g/L, 115g/L, 120g/L, 125g/L or 130g/L, etc.), sulfuric acid and not more than 10mg/L (such as 10mg/L, 5mg/L, 2mg/L, 1mg/L, 0.5mg/L or 0.1mg/L, etc.) chloride ions per L of electrolyte.

The additive comprises an agent A and an agent B, wherein the agent A comprises 50-200mg/L (such as 50mg/L, 100mg/L, 150mg/L or 200mg/L, etc.) of hydroxyethyl cellulose, 10-100mg/L (such as 10mg/L, 20mg/L, 50mg/L, 80mg/L or 100mg/L, etc.), 40-60mg/L (such as 40mg/L, 45mg/L, 50mg/L, 55mg/L or 60mg/L, etc.), 20-60mg/L (such as 20mg/L, 25mg/L, 30mg/L, 35mg/L, 40mg/L, 45mg/L, 50mg/L, 55mg/L or 60mg/L, etc.), alkylated polyethylene imine and 10-30mg/L (such as 10mg/L, 15mg/L, 20mg/L, 25mg/L or 30mg/L, etc.) of fatty amine ethoxysulfonate based on each L of electrolyte.

The molecular weight of the polyethylene glycol is preferably 6000 to 8000.

It should be noted that, if the molecular weight of polyethylene glycol is too low, the polarization will be insufficient; if the molecular weight of polyethylene glycol is too high, the interaction force between PEG molecules is large, the thickness of a diffusion layer is low, and surface defects such as uneven chromaticity and mottle are easily generated, although the polarization effect is stronger.

The agent B comprises at least one of 5.0-10.0mg/L (such as 5mg/L, 6mg/L, 7mg/L, 8mg/L, 9mg/L or 10mg/L, etc.) of sodium polydithio-dipropyl sulfonate, 20.0-100.0mg/L (such as 20mg/L, 50mg/L, 80mg/L or 100mg/L, etc.) of sodium 3-mercapto-1-propane sulfonate, 1.0-10.0mg/L (such as 1mg/L, 2mg/L, 5mg/L, 8mg/L or 10mg/L, etc.) of N, N-dimethyl-dithio-carbonyl sodium propane sulfonate and 2.0-6.0mg/L (such as 2mg/L, 3mg/L, 4mg/L, 5mg/L or 6mg/L, etc.) of tetrahydrothiazole thioketone.

Further, the additive may also include a C agent, which may illustratively include at least one of 0.5-5.0mg/L (e.g., 0.5mg/L, 1mg/L, 2mg/L, 3mg/L, 4mg/L, or 5mg/L, etc.) of a thiazabenzene derivative, 0.5-5.0mg/L (e.g., 0.5mg/L, 1mg/L, 2mg/L, 3mg/L, 4mg/L, or 5mg/L, etc.) of an azapyridine derivative, and 0.5-5.0mg/L (e.g., 0.5mg/L, 1mg/L, 2mg/L, 3mg/L, 4mg/L, or 5mg/L, etc.) of a substituted hydrazine derivative.

Wherein the thiazabenzene derivative may be, for example, a phenothiazine derivative; the pyridine derivative may be, for example, a phenazine derivative; the substituted hydrazine derivative may be, for example, a 2-hydrazono-2, 3-dihydrothiazole derivative.

On the basis, the agent A mainly plays a role in wetting, the agent B mainly plays a role in brightening, and the agent C can play a role in improving the elongation and leveling.

The copper foil is deposited by the electrolyte containing the agent A, the agent B and the agent C with the specific dosage, so that the obtained copper foil has no pinholes, low warpage, fine and smooth rough surface cells, uniform structure and no obvious polishing scratches on the smooth surface.

For reference, the cathode titanium foil 3 used in the present application can be prepared by the following method: titanium oxide films are plated on the upper surface and the lower surface of the titanium foil substrate by adopting a surface oxidation mode.

Before surface oxidation, the titanium foil substrate may be mechanically polished or chemically polished (to ra=0.4-0.8), and then cleaned of surface residual polished impurities with water and blow dried.

In the present application, the surface oxidation method may include an anodic oxidation method or a high-temperature oxidation method.

When the anodic oxidation mode is adopted, the current used in the anodic oxidation process is in a direct current form or a pulse form. The anodic oxidation process may use a constant voltage reaction for a period of time until the current drops to zero, or a constant current step-up to a set voltage pattern.

The anodizing solution used is prepared from at least one of sulfuric acid, oxalic acid and lactic acid, or an electrolyte used for depositing the copper foil is adopted.

In the anodic oxidation process, the voltage can be 15-50V (such as 15V, 20V, 25V, 30V, 35V, 40V, 45V or 50V, etc.), the current can be 0.5-2A (such as 0.5A, 1A, 1.5A or 2A, etc.), and the treatment time can be 3-5min (such as 3min, 3.5min, 4min, 4.5min or 5min, etc.).

By performing anodic oxidation under the above conditions, an oxide film having a predetermined thickness and at the same time having higher compactness can be obtained. Specifically, the oxide film produced under the above conditions is observed to be uniformly blue, dark cyan or golden yellow with naked eyes.

When anodic oxidation is adopted, the peeled titanium foil 5 is conveyed into an oxidation tank through a conveyor belt to be subjected to complementary oxidation, and is recovered to an initial state for recycling.

When the high-temperature oxidation mode is adopted, the temperature can be 400-600 ℃ (such as 400 ℃, 450 ℃, 500 ℃, 550 ℃ or 600 ℃ and the like) and the treatment time can be 1-3h (such as 1h, 1.5h, 2h, 2.5h or 3h and the like) in the high-temperature oxidation process. The process may be performed in an oven.

In addition, the application also provides a copper foil which is produced by the copper foil production method.

The thickness of the copper foil is not more than 5 μm, such as 4.5 μm.

The obtained copper foil has no pinholes, low warpage, high strength and high toughness; through microscopic structure observation, the copper foil has fine rough surface unit cells, uniform structure and no obvious polishing scratch on the smooth surface.

The features and capabilities of the present invention are described in further detail below in connection with the examples.

Example 1

The present embodiment provides a copper foil production apparatus comprising an anode tank 2, a titanium anode plate 1, a cathode titanium foil 3, and a supporting means 6 for supporting the cathode titanium foil 3.

When the cathode titanium foil 3 passes through the passage, the distance between the upper surface of the titanium foil and the lower surface of the first titanium anode plate is 1cm, and the distance between the lower surface of the titanium foil and the upper surface of the second titanium anode plate is 1cm.

The upper and lower surfaces of the cathode titanium foil 3 each had a titanium oxide film with a thickness of 10 μm.

The support means 6 comprise 2 sets of first support members, the 2 sets of first support members being arranged in the anode channels 2 and being located at the inlet and outlet ends of the channels, respectively. Each group of first supporting components respectively comprises a matched upper supporting piece and a matched lower supporting piece, wherein the upper supporting piece is used for being abutted with the upper surface of the cathode titanium foil 3, and the lower supporting piece is used for being abutted with the lower surface of the cathode titanium foil 3.

The supporting device 6 further comprises 3 groups of second supporting components, all the second supporting components are arranged outside the anode tank 2, wherein 1 group of second supporting components are arranged at the position of entering the anode tank 2, and the other 2 groups of second supporting components are arranged at the position of exiting the anode tank 2.

The supporting pieces are all bearings.

Example 2

The present embodiment provides a copper foil production method, which is produced by using the copper foil production apparatus provided in embodiment 1, specifically, under the electrolysis condition, the cathode titanium foil 3 is passed through the anode tank 2 and the channel at a constant speed of 5m/min, and copper foil is deposited on the surface of the cathode titanium foil 3 at a position opposite to the middle of two parallel anode plates in the passing process. Subsequently, the cathode titanium foil 3 deposited with the copper foil is peeled off and rolled up. The cathode titanium foil 3 obtained after the peeling is subjected to oxidation treatment again for recycling.

The electrolyte used for depositing the copper foil is a copper sulfate system electrolyte, and comprises a basic component and an additive, wherein the additive comprises an agent A, an agent B and an agent C.

The basic components comprise 355g/L copper sulfate, 115g/L sulfuric acid and 5mg/L chloride ions per L electrolyte. The agent A comprises 100mg/L hydroxyethyl cellulose, 50mg/L polyethylene glycol (molecular weight is 5000), 50mg/L polypeptide protein, 40mg/L alkylated polyethylenimine and 20mg/L fatty amine ethoxysulfonate. The agent B comprises 7mg/L sodium polydithio-dipropyl sulfonate, 60.0mg/L sodium 3-mercapto-1-propane sulfonate, 5mg/L N, N-dimethyl-dithio carbonyl sodium propane sulfonate and 4.0mg/L tetrahydrothiazole thioketone. Agent C comprises 2.5mg/L phenothiazine derivative, 2.5mg/L phenazine derivative, and 2.5 mg/L2-hydrazono-2, 3-dihydrothiazole derivative.

The thickness of the resulting copper foil was 4.5. Mu.m.

Example 3

This example provides a method for preparing the cathode titanium foil 3 of example 1.

The method comprises the following steps: mechanically polishing the titanium foil substrate until Ra=0.4-0.8, then cleaning the surface residual polishing impurities with water, and drying.

And plating titanium oxide films on the upper surface and the lower surface of the titanium foil substrate by adopting an anodic oxidation mode.

The current used in the anodic oxidation process is in a direct current form; the anodizing solution was the electrolyte used to deposit the copper foil in example 2; the voltage was 30V, the current was 1A, and the treatment time was 4min.

Test examples

Taking the copper foil obtained in example 2 as an example, photographs of the copper foil obtained after peeling are shown in fig. 2 and 3, wherein fig. 2 is a top view and fig. 3 is a plan view. As can be seen from fig. 2 and 3, the resulting copper foil is pinhole-free and low in warpage.

Further, the copper foil obtained in example 2 was subjected to microstructure observation, and the results showed that: the obtained copper foil has fine and smooth rough surface unit cells, uniform tissue and no obvious polishing scratch on the smooth surface.

Comparative example 1

The titanium foil of example 2 was replaced with a cathode roll, and the copper foil obtained had a thickness of 4.5 μm under the same production conditions, and the photographs thereof were shown in FIGS. 4 and 5, wherein FIG. 4 is a top view and FIG. 5 is a plan view. As can be seen from fig. 4 and 5, the resulting copper foil is significantly warped.

In summary, the electrolytic copper foil prepared on the basis of the titanium oxide surface has the advantages that the thickness of the obtained copper foil is not limited by the grain size of the titanium matrix, and the electrolytic copper foil has absolute advantages in the production of ultra-thin or even ultra-thin copper foil. In addition, the production mode of double-sided deposited copper foil greatly improves the production efficiency. The copper foil deposited on the oxide film has the advantages of no pinholes and low warpage, and can be high-strength and high-toughness ultrathin copper foil by combining the specific additive. By microstructure characterization, the copper foil has fine rough surface unit cells, uniform structure and no obvious polishing scratch on a smooth surface.

The above is only a preferred embodiment of the present invention, and is not intended to limit the present invention, but various modifications and variations can be made to the present invention by those skilled in the art. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for producing a copper foil, comprising: adopting copper foil production equipment to carry out production;

the copper foil production equipment comprises an anode tank, a titanium anode plate and a cathode titanium foil;

the titanium anode plates comprise a first titanium anode plate and a second titanium anode plate which are arranged in parallel up and down, a channel for passing a cathode titanium foil is formed between the first titanium anode plate and the second titanium anode plate, and the first titanium anode plate and the second titanium anode plate are both positioned in the anode tank;

the upper surface and the lower surface of the cathode titanium foil are provided with titanium oxide films, and the cathode titanium foil is used for depositing copper foil in the process of passing through the channel;

the distance between the lower surface of the first titanium anode plate and the upper surface of the second titanium anode plate is 1-3cm;

the thickness of the titanium oxide film on the upper surface and the lower surface of the cathode titanium foil is 5-20 mu m;

under the electrolysis condition, enabling the cathode titanium foil to uniformly pass through the channel and depositing copper foil on the surface of the cathode titanium foil in the channel in the passing process; the passing speed is not more than 10m/min;

the electrolyte used for depositing the copper foil is a copper sulfate system electrolyte; the copper sulfate system electrolyte comprises a basic component and an additive;

wherein the base component comprises 350-360g/L copper sulfate, 100-130g/L sulfuric acid and not more than 10mg/L chloride ions per L electrolyte;

the additive comprises an agent A and an agent B, wherein the agent A comprises at least one of 50-200mg/L of hydroxyethyl cellulose, 10-100mg/L of polyethylene glycol, 40-60mg/L of polypeptide protein, 20-60mg/L of alkylated polyethylenimine and 10-30mg/L of fatty amine ethoxysulfonate; the agent B comprises at least one of 5.0-10.0mg/L of sodium polydithio-dipropyl sulfonate, 20.0-100.0mg/L of 3-mercapto-1-propane sodium sulfonate, 1.0-10.0mg/L N, N-dimethyl-dithiocarbonyl sodium propane sulfonate and 2.0-6.0mg/L of thiazolidinedione;

the additive also comprises a C agent, wherein the C agent comprises at least one of 0.5-5.0mg/L of thiazabenzene derivative, 0.5-5.0mg/L of azapyridine derivative and 0.5-5.0mg/L of substituted hydrazine derivative.

2. The method of producing a copper foil according to claim 1, wherein the copper foil production apparatus further comprises a supporting means for supporting the cathode titanium foil;

the supporting device comprises at least one group of first supporting components, and all the first supporting components are arranged in the anode tank and support the part of the cathode titanium foil positioned in the anode tank.

3. The method of producing copper foil according to claim 2, wherein each of the first support members includes a mating upper support member for abutting against an upper surface of the cathode titanium foil and a mating lower support member for abutting against a lower surface of the cathode titanium foil.

4. The method of claim 3, wherein the inlet and outlet ends of the passage are each provided with at least one set of the first support members.

5. The method of producing copper foil according to claim 2, wherein the supporting means comprises at least one set of second supporting members, all of which are disposed outside the anode tank and support the portion of the cathode titanium foil located outside the anode tank.

6. The method of producing a copper foil according to claim 1, wherein the passing speed is 2 to 6m/min.

7. The method for producing copper foil according to claim 1, wherein the cathode titanium foil is produced by: titanium oxide films are plated on the upper surface and the lower surface of the titanium foil substrate by adopting a surface oxidation mode.

8. The method of producing copper foil according to claim 7, wherein the surface oxidation means comprises anodic oxidation means or high temperature oxidation means.

9. The method of producing copper foil according to claim 8, wherein the current used in the anodic oxidation is in the form of direct current or pulse.

10. The method according to claim 9, wherein the anodizing solution used in the anodizing process is prepared from at least one of sulfuric acid, oxalic acid and lactic acid, or an electrolyte used for depositing the copper foil is used.

11. The method of claim 9, wherein the anodic oxidation is performed at a voltage of 15-50V, a current of 0.5-2A, and a treatment time of 3-5min.

12. The method of producing copper foil according to claim 11, wherein the high temperature oxidation process is performed at 400 to 600 ℃ for 1 to 3 hours.

13. The method of producing copper foil according to claim 8, further comprising mechanically polishing or chemically polishing the titanium foil substrate before the surface oxidation.

14. The method of producing a copper foil according to any one of claims 1 to 13, further comprising peeling and winding the cathode titanium foil deposited with the copper foil.

15. The method of producing copper foil according to claim 14, further comprising: and (3) oxidizing the cathode titanium foil obtained after stripping again for recycling.

16. A copper foil produced by the copper foil production method according to any one of claims 1 to 15.

17. The method of producing a copper foil according to claim 16, wherein the thickness of the copper foil is not more than 5 μm.